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What are the formulas for the upper and lower quantiles?

In a sample population containing a set of data values sorted in increasing order, a "median" refers to the middle value. The upper quartile is the median of the upper half, while the lower quartile is the median of the lower half of the set. By subtracting the lower quartile from the upper quartile, the interquartile range is calculated.

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What is the formula for finding the median of ungrouped data?

To determine the median of ungrouped data with N elements, one should first order the data from lowest to highest. The median is determined by finding either the middle element in the data or the average of the middle two elements, depending on whether there are an odd or even number of elements in the data.\nFor example, suppose a set of data has the numbers {4, 8, 7, 10, 100}. First, one would reorder the elements from lowest to highest so that it appears as {4, 7, 8, 10, 100}. There are an odd number of elements in the set; i.e. N=5. Since (5+1)/2 = 3, in this case, the third element in the..

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How do you find the altitude of a triangle?

The altitude of a triangle is the line segment from any vertex of a triangle that is perpendicular to the side opposite of the vertex. The altitude of any triangle is easy to draw, but finding the length of the altitude can be difficult for triangles that aren't right triangles. Use the following steps to determine the length of the altitude for non-right triangles. If the area of the triangle is not a given value, then the length of the altitude must be determined using trigonometry.Determine the length of the base of the triangleThe base of the triangle, in this case, will be the side o..

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What number is higher than a trillion?

It is difficult for a human mind to grasp the concept of 1 trillion, and the standard numerical depiction of the number, 1,000,000,000,000, is difficult to work with in equations. This is why the number, and most of the numbers above it, is often represented exponentially as 10^12. Higher numbers can be represented either as multiples of 10^12, such as 2.5 x 10^12, which equals 2,500,000,000,000, or as higher exponents such as 10^15, which is a quadrillion.\nIn long-form number systems, such as that used in continental Europe, 1 trillion is equal to 10^18, or 1 quintillion in the United States..

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What would your grade be if you got four questions wrong out of 20?

For example, many teachers use a plus-or-minus grading system, where an 80 percent corresponds to a B- letter grade, and an overall score of 80 percent in a course corresponds to 2.75 grade points. Additionally, some teachers may use entirely different cutoffs for assigning letter grades. Some teachers grade tests on a curve when they find that a test is too difficult for the class and allot points to every student's final grade to adjust the class average as necessary. Most professors at the college level include information about their grading systems in the syllabus for each course.

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How do you determine if data is normally distributed?

Normal distribution of data is a popular concept used in the field of social sciences. It is best suited for data that meets several conditions. First, there must be a strong tendency for data to take on a central value. Second, there must be an equal likelihood of positive and negative deviations from this value. Finally, the frequency of the deviations must fall off rapidly while moving away from the central value. Unlike other distributions, such as the logistic and Cauchy distributions, the likelihood of having extreme values that deviate from the central data value are rare. Because of th..

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What is 5+5+5=550?

This is a very simple riddle because the plus sign just has to be reworked into a 4 to make the solution work. It can fool many people though because the equation at first just looks erroneous.\nA similar riddle could be 3+3+7=350. Adding a straight line to one of the plus signs will change it to a four, fixing the equation. These types of brain teasers are common in logic books and collections of mind exercises.

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How do I calculate the percentage of something?

The word percent means "for every hundred," so finding a percent is the same as restating a rational number so that its denominator is 100. The ratio 14/50 can be converted to a percent by multiplying the numerator and denominator by 2, yielding the ratio 28/100, or 28 percent. Decimal numbers are converted to percents by moving the decimal point two places to the left. For example, 0.73 equals 73 percent.

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How do you solve a problem when you have different bases with the same exponents?

The reason it is possible to combine the bases when dealing with multiplication and division is due to the commutative property of multiplication and division, which means that changing the order of the operations doesn't change the result. For instance, X raised to the third power times Y raised to the third power is the same as XXXYYY, which is the same as XY raised to the third power. However, if the exponents are different, this doesn't hold true.\nIn multiplication and division, when the bases are the same and the exponents are different, the exponents can be added or subtracted..

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What is the perimeter of a square with an area of 49 inches?

The square root of 49, or 7 inches, is then the length of one side. The formula for the perimeter of a square is the sum of all sides. Since all sides are 7 inches, the perimeter is 7 + 7 + 7 + 7, or 28 inches. The area of the square is reported in square inches because inches are multiplied by inches to yield square inches.

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